There are two groups of Pedelecs and a main distinction between them is the maximum speed at which the rider receives assistance from the electric motor.
For conventional Pedelecs, the maximum assisted speed is approximately 15.5 mph (25 kph). For high-speed Pedelecs (or S-Pedelecs) it is approximately 28 mph (45 kph).
Electric bikes in the UK have a maximum continuous rated power of 250W (although this is muddied by our own legislation – see UK electric bike law). The power output is progressively reduced and finally cuts out as the bike reaches the speed of 15.5 mph or if the rider stops pedalling. Helmets are not mandatory and you don’t require insurance. You can also make use of all the general cycling facilities including cycle paths.
type approval is required
insurance is mandatory (evidence must be displayed on the bike)
moped driving licence is required
must be ridden on the road (no cycle paths!)
suitable protective helmet (most likely a motorcycle helmet)
beefier braking system, lighting and signalling and tyres (as specified in EU directive)
rear view mirrors
500W maximum power